This invention relates to soil working tools for agriculture. More particularly, this invention relates to an apparatus and method of removing and replacing soil openers on the shanks of an agricultural soil working implement such as a cultivator, an air drill or a chisel plow.
In today""s farms a standard implement to disturb the soil for cultivating is a framed cultivator implement generally supported by wheels and pulled by a substantial power source such as a four wheel drive tractor. A standard cultivator generally is equipped with a substantially horizontal frame which a number of cross members positioned transverse to the direction of travel. Located on the cross-members are a plurality of standard curved steel shanks which extend downwardly. The shanks are generally equipped with a pair of apertures so that the soil working tools can be bolted onto such shanks.
Soil working tools can be openers, knives or sweeps depending upon the operation. The soil working tools generally have a shorter life than the cultivator due to the constant contact with rocks and other obstacles in the field. Thus, these must be changed from time to time. In addition, new types of farming require different sizes of furrows or trenches cut in the ground by such earth working tools. For example in zero tillage operations only a narrow furrow need be cut into the stubble and seed placed therein. In other cases a wider trench may be necessary or in cases of summer fallow or reseeding, for instance a hay field, the entire ground must be turned over in preparation for crop planting.
Typically when a farmer replaces the soil openers or changes soil openers to a different type, it is necessary to unbolt each one of the soil openers, such bolts often becoming rusty and extremely hard to remove. This is a very time consuming operation and can take as long as a couple of days depending upon the number of soil working tools which have to be removed and then replaced by removing nuts and bolts.
More recently, a type of adapter is bolted to the shank of the cultivator and the soil working tool having a shank of configuration similar to the adapter is hammered on by friction and hammered off by friction due to the tapered nature of the mating surfaces. This solution, although much improved from the former method still has several drawbacks. For example, soil working tools could slide of the adapter in the fields. In other cases, the amount of force required to remove such soil working tool is immense and problems are encountered trying to remove the soil working tools without damaging the shanks or adapters.
Thus, a need still exists for an easy method of removing and replacing soil working tools on the shanks of cultivators and ensuring that they are locked in place.
The concept of removing and replacing earth working tools from machinery is not new. For example, in U.S. Pat. No. 4,611,418, a trenching machine had a large rotating wheel coupled to the bucket. The bucket is coupled to tapered nose pieces and digging points are placed on the nose pieces. The configuration of a machine, however, is not compatible with agriculture seeding and planting. In U.S. Pat. No. 4,611,418, a blocking member is encased in a flexible ceiling member.
In U.S. Pat. No. 3,041,752, teeth are located on the buckets of wheels. Next to the bucket, is a pocket member within which the tooth fits. There is also a coiled spring in a slot which by friction, has a means for resiliently biasing the upper face of the tooth shank (3) into tight frictional engagement with the top face (6b) of slot (6). A pin must be removed prior to removal of the spring and tooth.
In U.S. Pat. No. 3,061,021 a xe2x80x9cCultivatorxe2x80x9d tool support or holder has a socket in which the shank or the tang of the cultivator shovel is inserted and automatically releasably locked in the operating position. The patent uses a leaf spring with a recess on top of the shank.
In U.S. Pat. No. 3,220,488, the patent discloses an elongated depending cultivator shank having a sweep which includes an elongate tongue. A cultivator shank includes a pair of depending elongated side walls. The patent uses a pivoted latch member, pivot pins, locking doves and expansion springs.
In U.S. Pat. No. 2,908,340 the cultivator shank is equipped with pins and locking arms. The locking arms have lips or slots. There is a plurality of key hole openings and a plurality of locking arms pivotally connected.
U.S. Pat. No. 5,007,484 describes a soil cultivator with a plow or sweep being held to the shank by a movable snap action lock. The shank of the sweep is a pair of C-shaped sections having open sides which face one another. The sweep fits directly on the working end of the shank of the cultivator. A sheet metal clip is used. All forces are transmitted directly from the shank of the cultivator abutment end to a blade stop 52.
The Inventors of the present invention have made an improvement over the prior art devices which has proved to be simple to manufacture and very adaptable. By using an adapter for the quick release device, a standard cultivator can either be used with the adapter and quick release mechanism of the present invention or can be returned to normal use having tools bolted thereon. Thus the present invention, through the use of the unique adapter can be used on any cultivator currently in the market place.
The adapter of the present invention is somewhat T-shaped having a head and a lower shank. It has two large apertures which permit it to be bolted permanently to the shank of a cultivator. From an end view, the adapter has a flat top and a flat bottom, in cross section. It has a pair of downwardly tapered sides which meet upwardly tapered sides.
The adapter has a type of T-shaped head, such that when the C-shaped hollow shaft of the soil working tool, having a similar configuration to the cross section of the adapter is moved upwardly and onto the adapter, the extending flanges of the head prevent the shank of the soil working tool from moving any further outwardly. In the middle of the adapter is a detent adapter aperture into which is placed a filler plug. A resilient ball keeps upward pressure on the detent which is housed within the filler plug.
In a different embodiment the adapter is equipped with a longitudinal slot on its topside which extends from the top of the head of the adapter to the upper bolt aperture. This is a provision for a removal tool slot engagement point. The removal tool in this embodiment facilitates the depression of the detent and consequent removal of the shank of the sweep or soil working tool.
The sweep, knife, or soil working tool, is equipped with a type of U-shaped upper shank, having an open bottom side and an aperture through the mid section of the shank. The inner sides of the U-shaped shank is of the same configuration as the outer sides of the adapter shank and thus can move easily upwardly without a great deal of friction. The aperture in the shank is adapted to receive the detent in the locked position.
Therefore, this invention seeks to provide a quick change soil working assembly adapted for use with an agricultural soil working implement; said assembly comprising an adapter and a soil working tool; said adapter being configured to be fixedly attached in operation to a mounting shank on said implement; said adapter including a shank and a head; said adapter shank having a cross-section adapted to matingly engage said soil working tool; said adapter shank including a pair of a bolt apertures, a detent aperture, and a resiliently biased detent assembly; said detent assembly including a resilient means, a detent aperture filler plug, and a detent; said soil working tool, including a soil working portion and an elongate holder; said holder including a pair of side flanges with an inner cross section adapted in operation to matingly engage said adapter shank; said holder further including a detent receiving aperture; whereby, in operation, when said holder is moved longitudinally onto a mounted position on said adapter shank, said detent means registers with said aperture whereupon said resilient means moves said detent into said detent receiving aperture to lock said soil working tool in place; and when said detent is pressed downwardly said holder may be moved longitudinally of said adapter shaft to detach said soil working tool.
The invention further seeks to provide a quick change soil working assembly wherein an adapter includes a longitudinal recess on the top side thereof, said recess being adapted to receive a curved end of a removal tool.